Methods and guide members to transfer a wheel assembly

ABSTRACT

Methods and guide members to transfer a wheel assembly are disclosed. An illustrated method employs using the guide member to displace the wheel assembly relative to an axle assembly to maintain a continuous linear alignment of the wheel assembly with the axle assembly.

FIELD OF THE DISCLOSURE

This disclosure relates generally to methods and guide members to transfer a wheel assembly and, in particular, to methods and guide members to transfer the wheel assembly relative to an axle assembly to maintain a continuous linear alignment of the wheel assembly with the axle assembly.

BACKGROUND

Typically, an aircraft wheel assembly and an associated brake assembly (e.g., a wheel and brake assembly) are designed for easy transfer onto or off an axle assembly. Usually the wheel assembly has a pair of axially spaced-apart bearing assemblies which position rotatably the wheel and brake assembly upon the axle assembly during operation of the aircraft. The axle assembly includes an axle sleeve surrounding the axle, and an axle end with threads extending axially beyond the axle sleeve. Typically, a brake guide member is used to mount the brake assembly upon the axle assembly at a lateral position toward the inboard end of the axle sleeve. The piston housing and the torque tube pedestal of the brake assembly have inner diameter portions that engage large diameter parts of the inboard end of the axle sleeve. The brake guide is removed prior to the transfer of the wheel assembly. During the transfer and handling of the wheel assembly relative to the axle assembly, the wheel assembly may not be linearly aligned continuously with the axle assembly. This misalignment of the wheel assembly may cause one or both of the inboard (IB) or outboard (OB) bearing assemblies to engage and damage the threads at the axle end. During the transfer of the wheel assembly onto the axle assembly, the engagement of the OB bearing assembly with the threads and/or the axle sleeve end may also cause the outboard grease seal to unseat and result in the unseating or separation of the OB bearing assembly from the wheel assembly. In a similar manner, during the removal of the wheel assembly from the axle assembly, the engagement of the IB bearing assembly with a bearing land on an axle sleeve can cause the IB grease seal to unseat and result in the unseating or separation of the IB bearing assembly from the wheel assembly. All of these problems can occur as a result of the wheel assembly not remaining in linear alignment with the axle during the transfer of the wheel assembly. Additionally, the transfer of a non-braked wheel assembly (i.e., a wheel assembly that does not contain therein a brake assembly) onto or off of an axle assembly may also experience the same problems.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional illustration of an example aircraft wheel and brake assembly mounted on an axle sleeve located about an axle.

FIG. 2 is a cross-sectional illustration of an example non-braked wheel assembly.

FIG. 3 is a cross-sectional illustration of an example guide member.

FIG. 4 is a depiction of the example guide member being employed to transfer a non-braked wheel assembly relative to an axle assembly.

FIG. 5 is a flow diagram of an example process or method to transfer a wheel assembly relative to an axle assembly by using a guide member to maintain continuous linear alignment of the wheel assembly with the axle assembly.

DETAILED DESCRIPTION

The example methods and guide members to transfer a wheel assembly disclosed herein may be utilized with various types of wheel assemblies mounted on various types of axles or axle assemblies. Additionally, while the examples disclosed herein are described in connection with aircraft applications in the aerospace industry, the examples may also be more generally applicable to a variety of braking applications in different industries.

FIG. 1 is a cross-sectional illustration of an example aircraft wheel and brake assembly 100 mounted on an axle assembly 400. The example aircraft wheel and brake assembly 100 of FIG. 1 includes a wheel assembly 110 and a brake assembly 210 located within the wheel assembly 110. The wheel assembly 110 includes an inboard wheel half 120 and an outboard wheel half 130 fastened together by a plurality of wheel bolts and nuts 140. The inboard wheel half 120 includes a wheel well 122 about which are located a plurality of circumferentially spaced-apart rotor drive keys 124. The inboard wheel half 120 also includes a wheel hub 126 housing an inboard bearing assembly 150. The inboard bearing assembly 150 includes an inner race 152, a plurality of roller bearings 154, an outer race 156, and an inboard grease seal 158. The outboard wheel half 130 includes a wheel well 132 and a wheel hub 136 housing an outboard bearing assembly 160. The outboard bearing assembly 160 includes an inner race 162, a plurality of roller bearings 164, an outer race 166, and an outboard grease seal 168.

The brake assembly 210 of the illustrated example is contained within the inboard wheel half 120 and includes a piston housing 212 having therein a plurality of piston assemblies 214, a torque take-out connection 215 for connection to a landing gear torque take-out arm (not shown), one or more hydraulic connections 217 (only one shown) for connection with a hydraulic braking system (not shown), a torque tube 220 attached to the piston housing 212 by a plurality of bolts and nuts 216, and a brake disc assembly 218 having carbon-carbon composite brake discs. The torque tube 220 includes a plurality of splines 222, a backing flange 224, and a torque tube pedestal or foot 226 adjacent a bushing assembly 228. The brake disc assembly 218 includes a plurality of stator discs 230, a nonrotating pressure plate disc 232, and a nonrotating backing plate disc 234, all located on the torque tube 220. Each of the stator discs 230, the pressure plate disc 232, and the backing plate disc 234, has a plurality of slots 236 receiving the splines 222 of the torque tube 220. The brake disc assembly 218 also includes a plurality of rotor discs 240 interleaved with the stator discs 230. Each rotor disc 240 has a plurality of slots 242 located about an outer circumference of the rotor disc 240. The slots 242 of the rotor discs 240 receive the drive keys 124 to attach nonrotatably the rotor discs 240 to the wheel assembly 110.

In the example illustrated in FIG. 1, the example aircraft axle assembly 400 of an aircraft landing gear (not shown) includes an axle 410 having axle threads 412, and an axle sleeve 420. The axle sleeve 420 has a pair of axially spaced-apart bearing lands 422 and 424, and a reduced diameter, axially-extending portion 425 located between the bearing land 422 and the bearing land 424. A curved step 428 is located at the transition of the reduced diameter, axially-extending portion 425 to the bearing land 424. An axle sleeve end 429 is adjacent the bearing land 424. When the wheel and brake assembly 110 is mounted upon the axle assembly 400, the inboard bearing assembly 150 is supported upon the bearing land 422 and, similarly, the outboard bearing assembly 160 is supported upon the bearing land 424.

FIG. 2 is a cross-sectional illustration of an example non-braked wheel assembly 310. Structures in FIG. 2 which are similar to or the same as structures in FIG. 1 are identified by the same reference numerals increased by 200, and will not be further described herein. Although similar in design to the example wheel assembly 110 shown in FIG. 1, the example non-braked wheel assembly 310 does not include a brake assembly such as, for example, the brake assembly 210 illustrated in FIG. 1. Generally, non-braked wheel assemblies are mounted on axle and landing gear assemblies to provide for the support and/or steering of an aircraft. For example, non-braked wheel assemblies may be used on either aircraft body landing gear in the aft position or nose landing gear.

In operation, the example aircraft wheel and brake assembly 100 of FIG. 1 or the example non-braked wheel assembly 310 of FIG. 2, is mounted on the axle assembly 400 of the aircraft landing gear. As is well-known for hydraulic brake assemblies such as, for example, the brake assembly 210, the piston housing 212 of the aircraft wheel and brake assembly 100 in FIG. 1 is coupled via the hydraulic connection 217 to a hydraulic brake actuation system (not shown) of an aircraft (not shown). When an aircraft operator actuates a brake pedal of the aircraft or when the brakes are operated automatically by the aircraft's hydraulic brake actuation system, pressurized hydraulic brake fluid is communicated to the hydraulic connection 217 to cause pistons of the piston assemblies 214 to extend from the piston housing 212 and squeeze together the spinning rotor discs 240 and the nonrotating stator discs 230 between the pressure plate disc 232 and the backing plate disc 234, thereby causing the spinning rotor discs 240 and attached wheel assembly 110 to decelerate and slow down the aircraft until it is brought to a stop. Persons of ordinary skill in the art will really understand that, for other applications, the illustrated aircraft wheel and brake assembly 100 of FIG. 1 may include different types of brake discs such as, for example, cerametallic brake discs, the brake assembly 210 may be an electric aircraft brake assembly that utilizes electro-mechanical actuators instead of the hydraulic piston assemblies 214, or the brake assembly may be operated by an electrical actuation system instead of the hydraulic brake actuation system.

The example non-braked wheel assembly 310 of FIG. 2 can be mounted in similar manner to the axle assembly 400 in FIG. 1, except that there are not any hydraulic connections because the wheel assembly 310 does not have therein a brake assembly such as, for example, the brake assembly 210 in FIG. 1. As previously disclosed, the non-braked wheel assembly 310 is used primarily for the support and/or steering of the aircraft.

FIG. 3 is an illustration of an example guide member 500 which may be used to transfer a wheel assembly or a wheel and brake assembly relative to an axle assembly and, in particular, to accomplish the transfer while maintaining a continuous linear alignment of the wheel assembly or the wheel and brake assembly with the axle assembly. The example guide member 500 includes a hollow body 502 having a through opening 503, a continuous outer surface 504, an end 506 having threads 508 located internally at an end opening 510, and an opposite end 511 having a cone-shaped outer surface 512 extending to an initial outer diameter 513 adjacent an end opening 514. The example body 502 of FIG. 3 also defines a set of circumferentially spaced-apart through openings 516. Although the example guide member 500 is illustrated as a hollow body 502, it may be implemented, for example, in the form of a solid body, or a solid body with a partial longitudinal opening in the body.

As depicted in FIG. 4, the guide member 500 is attached to the axle 410 by engaging the threads 508 with the axle threads 412 of the axle 410. A turning rod or tool (not shown) having one or more extensions received, respectively, in the through openings 516, may be utilized to rotate the guide member 500 so the threads 508 fully engage the axle threads 412 (see FIG. 4) to attach securely the guide member 500 to the axle 410 of the axle assembly 400. Once attached to the axle 410, the guide member 500 of the illustrated example is in linear alignment with the axle 410, and remains continuously in linear alignment as long as the guide member 500 is attached to the axle 410. The non-braked wheel assembly 310 of FIG. 2 or the wheel and brake assembly 100 of FIG. 1 may then be transferred onto the axle assembly 400 via the guide member 500. Although the transfer of the non-braked wheel assembly 310 relative to the axle assembly 400 is described below, the wheel assembly 110 or the wheel and brake assembly 100 of FIG. 1 may be transferred in the same manner relative to the axle assembly.

As depicted in FIG. 4, the non-braked wheel assembly 310 has been moved laterally in the direction of arrow 600 so that the inboard bearing assembly 350 has received the cone-shaped outer surface 512 of the guide member 500. The initial outer diameter 513 of the end 511 is smaller than the diameter of the inner race 352 of the bearing assembly 350, thus assisting in the reception of the end 511 within the inboard bearing assembly 350. As can be readily seen in FIG. 4, the wheel assembly 310 has been moved laterally in the direction of arrow 600 relative to the guide member 500 until at least the outboard bearing assembly 360 was received on the continuous outer surface 504. The guide member 500 of the illustrated example has a length at least equal to or greater than the distance between the bearing assemblies 350 and 360 so that the wheel assembly 310 may be positioned entirely on the guide member 500. The length of the example guide member 500 may be, for example, sixteen to twenty inches. The engagement of the threads 508 of the guide member 500 with the axle threads 412 of the axle 410 and the example guide member 500 itself are structured to be strong enough to support fully the weight of the wheel assembly 310 of FIG. 2 or the wheel assembly 110 of FIG. 1, each with a tire mounted thereon (not shown).

When positioned upon the guide member 500 such that the inboard bearing assembly 350 and the outboard bearing assembly 360 are engaging the continuous outer surface 504, the wheel assembly 310 is in linear alignment with the axle assembly 400. The wheel assembly 310 may be transferred or moved further in the direction of the arrow 600 in FIG. 4, with or without a prior period of being positioned stationarily on the guide member 500, so that the bearing assemblies 350 and 360 slidingly engage the continuous outer surface 504 of the example guide member 500. As a result, the inboard bearing assembly 350 transfers smoothly to the bearing land 424 of the axle sleeve 420. As the wheel assembly 310 moves onto the axle sleeve 420, the inboard bearing assembly 350 passes over the axle threads 412 and the adjacent axle sleeve end 429 without being able to engage, and damage, those axle threads 412 and/or the adjacent axle sleeve end 429. As the wheel assembly 310 is moved further in the direction of arrow 600 in FIG. 4, the inboard bearing assembly 350 passes over the bearing land 424, over the reduced diameter, axially-extending portion 425 located between the bearing lands 422 and 424, and onto the bearing land 422.

During this movement, the outboard bearing assembly 360 engages slidingly the continuous outer surface 504 of the guide member 500, and then engages the bearing land 424 to enable the wheel assembly 310 to remain in continuous linear alignment with the axle assembly 400. Because the guide member 500 is attached to the axle threads 412 of the axle assembly 400, the wheel assembly 310 remains in continuous linear alignment with the axle assembly 400 and neither the inboard bearing assembly 350 nor the outboard bearing assembly 360 can engage, catch on, and/or damage the axle threads 412 and/or the axle sleeve end 429. Preventing the outboard bearing assembly 360 from engaging the axle threads 412 also prevents the grease seal 368 from being unseated and/or causing the outboard bearing assembly 360 to be unseated or separated from the wheel 310.

Once the wheel assembly 310 is fully transferred to or mounted upon the axle assembly 400, the guide member 500 may be detached from the axle 410 by utilizing the turning rod to rotate the guide member in the opposite direction. An axle nut assembly (not shown) is then threaded onto the axle threads 412 to retain the wheel 310 in operational position on the axle assembly 400.

To remove the wheel assembly 310 with a tire mounted thereon (not shown) from the axle assembly 400, the procedure disclosed above is reversed. Specifically, after removal of the axle nut assembly from the axle threads 412, the guide member 500 is attached to the axle assembly 400 by mating together the threads 508 and 412 and rotating the guide member 500. The wheel assembly 310 is then moved laterally in a direction opposite to the arrow 600 in FIG. 4, so that the outboard bearing assembly 360 engages slidingly the bearing land 424 and then the continuous outer surface 504 of the guide member 500. During the transfer or removal of the wheel assembly 310 from the axle assembly 400, the guide member 500 and the wheel assembly 310 remain in continuous linear alignment with the axle assembly 400. Thus, neither the outboard bearing assembly 360 nor the inboard bearing assembly 350 can engage, catch on, and/or damage the axle threads 412. The continuous linear alignment of the wheel assembly 310 with the axle assembly 400 also ensures that the inboard bearing assembly 350 slidingly engages smoothly the bearing land 422. It also ensures that the bearing assembly 350 does not catch on the step 428 of the axle sleeve 420 at the transition of the reduced diameter, axially-extending portion 425 to the bearing land 424.

In the absence of the guide member 500, the transfer of a wheel assembly such as, for example, the wheel assembly 310, from an axle assembly such as, for example, the axle assembly 400, may cause the wheel assembly 310 to tilt and misalign relative to the axle assembly 400. This tilting or misalignment occurs because the central portion or web of the wheel assembly 310 is heavy. As soon as the outboard bearing assembly 360 is off of the axle assembly 400, the weight causes the inboard bearing assembly 350 to catch or jam on the step 428 of the axle sleeve 420. The use of the guide member 500 prevents the inboard bearing assembly 350 from catching or jamming on the step 428 and also prevents the grease seal 358 from being unseated and causing the inboard bearing assembly 350 to be unseated from the wheel assembly 310 and remaining on the axle assembly 400.

Once the wheel assembly 310 has been transferred to the guide member 500, the wheel assembly 310 with a tire thereon (not shown) may remain positioned entirely upon the guide member 500. The wheel assembly 310 is removed periodically from the axle assembly 400 for the replacement of the tire and, thus, the wheel assembly 310 can be inspected while positioned on the guide member 500. When the wheel assembly 310 has been removed further or transferred from the guide member 500, the guide member 500 may be detached from the axle 410 by utilizing the turning rod to rotate the guide member 500 in the opposite (i.e., release) direction.

As previously described herein, the wheel assembly 110 in FIG. 1 may be transferred in the same manner relative to the axle assembly 400. A tire change is required more often than an overhaul of the entire wheel and brake assembly 100 (e.g., approximately three or four tire changes compared to one overhaul) and, thus, the brake assembly 210 need not be removed when the wheel assembly 110 is removed. The wheel assembly 110 in FIG. 1 may be transferred relative to the axle assembly 400 for a tire change in the same manner as the non-braked wheel assembly 310 is transferred. However, during the transfer of the wheel assembly 110, the torque take-out connection 215 may remain connected to the landing gear torque take-out arm so that brake assembly 210 may remain on the axle assembly 400. Alternatively, for an overhaul of both the wheel assembly 110 and the brake assembly 210, the entire wheel and brake assembly 100 may be transferred in the same manner relative to the axle assembly 400.

FIG. 5 is a flow diagram of an example process or method 700 to transfer a wheel assembly or a wheel and brake assembly relative to an axle assembly by using a guide member and, more particularly, to accomplish the transfer while maintaining continuous linear alignment of the wheel assembly or the wheel and brake assembly with the axle assembly. Initially, at block 702, a guide member (e.g., the example guide member 500 in FIG. 3) having a continuous outer surface (e.g., the example continuous outer surface 504) and an end (e.g., the end 514) attachable to an axle assembly (e.g., axle assembly 400 in FIG. 1) is provided. The guide member is attached in linear alignment with the axle assembly (e.g., the example guide member 500 is attached in linear alignment with the axle assembly 400 in FIG. 4), (block 704). A wheel assembly (e.g., the non-braked wheel 310 in FIG. 2) having spaced-apart bearing assemblies (e.g., the inboard bearing assembly 350 and the outboard bearing assembly 360 in FIG. 2) is displaced relative to the guide member (e.g., the displacement of the wheel assembly 310 in the direction of arrow 600 in FIG. 4) so the bearing assemblies engage slidingly the continuous surface of the guide member (e.g., the bearing assemblies 350 and 360 engaging slidingly the continuous surface 504 in FIG. 4) and the wheel assembly is aligned linearly with the axle assembly (e.g., the wheel assembly 310 is in linear alignment with the axle assembly 400 in FIG. 4), (block 706). The wheel assembly is then displaced to at least one of onto or off of the axle assembly (e.g., further displacement of the wheel assembly 310 either in the direction of or opposite to the arrow 600 in FIG. 4) depending on the application, (block 708). Then the guide member is detached from the axle assembly (e.g. the rotation and detachment of the guide member 500 relative to the axle assembly 400 in FIG. 4), (block 710).

An example method and guide member to transfer a wheel assembly have been described with reference to the flow chart illustrated in FIG. 5. However, persons of ordinary skill will readily appreciate that other methods may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined.

The example method 700 and the example guide member 500 disclosed in FIGS. 3 through 5 provide advantages over prior methods and articles. For example, a short length threaded end cap that threads onto and covers just the threads of the axle has been provided for the transfer of nose wheels. The example guide member 500 advantageously provides a continuous outer surface 504 for smooth sliding engagement of the guide member 500 with the bearing assemblies 150 and 160 or 350 and 360, the ability to position the wheel assembly 110 or 310 entirely upon the example guide member 500 at an off-axle position, and an easy transfer of the wheel assembly 110 or the wheel assembly 310 relative to the axle assembly 400. While being displaced relative to the axle assembly 400, the wheel assembly 110 or the wheel assembly 310 is maintained in continuous linear alignment with the axle assembly 400, thereby preventing both interference with the movement of the wheel assembly 110 or wheel assembly 310 and dislodgment of either of the bearing assemblies 150 and 160 or 350 and 360. Because the threads 508 of the guide member 500 engage the axle threads 412 of the axle 410, the axle threads 412 cannot be damaged by engagement with the bearing assemblies 150 and 160 or 350 and 360 during the mounting or dismounting process.

Additionally, the example guide member 500 is structured to support simultaneously both of the bearing assemblies 150 and 160 of the wheel assembly 110 or 350 and 360 of the wheel assembly 310, at off-axle positions while the guide member 500 is attached to the axle assembly 400. When attached to an axle assembly, neither the brake guide member nor the short length threaded end cap are capable of supporting entirely at off-axle positions the wheel assembly 110 or 310.

Although certain example methods apparatus and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents. 

1. A guide member to transfer a wheel assembly relative to an axle assembly, the wheel assembly having axially spaced-apart bearing assemblies, the guide member comprising: a body having an outer surface to maintain the wheel assembly in constant linear alignment with the axle assembly during displacement of the wheel assembly relative to the axle assembly, the body having a length enabling the axially spaced-apart bearing assemblies to be located simultaneously upon the guide member, a first body end attachable to the axle assembly; and a second body end opposite the first body end.
 2. A guide member as claimed in claim 1, wherein the second body end has a cone shape to guide the axially spaced-apart bearing assemblies onto the guide member.
 3. A guide member as claimed in claim 1, wherein the outer surface is continuous and permits unimpeded displacement of the bearing assemblies along the length of the continuous outer surface.
 4. A guide member as claimed in claim 1, wherein body includes a longitudinally-extending, constant diameter, cylindrical shape.
 5. A guide member as claimed in claim 1, wherein the body has an outer surface in substantial linear alignment with an adjacent bearing surface of the axle assembly.
 6. A guide member as claimed in claim 1, wherein the body defines therein a longitudinal through opening.
 7. A guide member as claimed in claim 1, wherein the axle assembly has threads at an end thereof and the first body end of the guide member is attachable to the axle assembly via the threads.
 8. A guide member as claimed in claim 7, wherein the wheel assembly is displaceable relative to the axle assembly without the bearing assemblies engaging the threads.
 9. A guide member as claimed in claim 1, further comprising at least one opening in the outer surface to receive a tool to rotate the body.
 10. A guide member as claimed in claim 1, wherein the axle assembly includes an axle and a sleeve located about the axle, the sleeve having a reduced diameter portion, the guide member maintaining the linear alignment of the wheel assembly with the axle assembly so that at least one of the bearing assemblies does not engage the reduced diameter portion.
 11. A guide member as claimed in claim 1, wherein when the first body end is attached to the axle assembly, the wheel assembly can be positioned upon and supported entirely by the guide member at an off-axle position.
 12. A guide member as claimed in claim 1, wherein the wheel assembly includes a brake assembly.
 13. A method to transfer a wheel assembly relative to an axle assembly, the wheel assembly having axially spaced-apart bearing assemblies, comprising: attaching a guide member to the axle assembly, the guide member having an outer surface in substantial linear alignment with the axle assembly; and displacing the wheel assembly relative to the axle assembly such that the bearing assemblies simultaneously engage slidingly the outer surface of the guide member with the wheel assembly in substantial linear alignment with the axle assembly.
 14. A method as claimed in claim 13, wherein displacing includes moving the wheel assembly to be located entirely on the guide member at an off-axle position or to be located only on the axle assembly.
 15. A method as claimed in claim 13, wherein the outer surface of the guide member comprises a constant diameter surface.
 16. A method as claimed in claim 13, wherein the axle assembly has a threaded end and the wheel assembly is displaced relative to the axle assembly without the bearing assemblies engaging threads of the threaded end.
 17. A method as claimed in claim 13, wherein the axle assembly has threads at an end thereof and attaching the guide member comprises threading the guide member onto the threads of the axle assembly.
 18. A method as claimed in claim 17, wherein an end of the guide member has a cone shape to assist in guiding the wheel assembly onto the guide member.
 19. A method as claimed in claim 13, wherein the guide member includes at least one opening in the outer surface to receive a tool to rotate the guide member to at least one of attach or detach the guide member to or from the axle assembly.
 20. A method as claimed in claim 13, wherein the axle assembly includes an axle having a sleeve located about the axle, the sleeve having a reduced diameter portion, the guide member maintaining the linear alignment of the wheel assembly with the axle assembly so that at least one of the bearing assemblies does not engage the reduced diameter portion.
 21. Method as claimed in claim 13, wherein the wheel assembly includes a brake assembly. 